A VOX circuit is simply a level activated switch, with the input to the level detector coming from a mic input. In fact, any sound loud enough will cause the transistor to turn on. Saying that, if you have the circuit that controls the motor ignore any input from the VOX while it is running for the 15 seconds then it solves the issue. On the other hand, if you want to stop and start it via VOX then I would suggest that you set the level where the opamp detects to high enough that you have to be really LOUD in order for it to trigger. Of course you could add a speech recognition so you say start and stop and it controls that way.... >From: Quah >Reply-To: pic microcontroller discussion list >To: PICLIST@MITVMA.MIT.EDU >Subject: EE : Need Help on VOX Interface with DC Motor >Date: Fri, 2 May 2003 08:26:00 -0700 > >I want to try to use the VOX circuit to turn on a dc motor in forward >and reverse for say, 15 sec. Then I want the output of the VOX be >isolated from the dc motor because the VOX output affected the >smoothness of the motor movement. > >Any idea how to isolate the motor from the VOX circuit when motor start >running but still able to turn on by VOX when motor stop ? > >The VOX circuit I am using is like this web page :- > >http://www.rason.org/Projects/basicvox/basicvox.htm > >-- >http://www.piclist.com hint: PICList Posts must start with ONE topic: >[PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads _________________________________________________________________ STOP MORE SPAM with the new MSN 8 and get 2 months FREE* http://join.msn.com/?page=features/junkmail -- http://www.piclist.com hint: PICList Posts must start with ONE topic: [PIC]:,[SX]:,[AVR]: ->uP ONLY! [EE]:,[OT]: ->Other [BUY]:,[AD]: ->Ads